DD144919A1 - PROCESS FOR PREPARING 2,5-DIARYL-3,4-DIARYLIMINO-1,2,5-THIADIAZOLIDINE S-OXIDES - Google Patents

Abstract

Such compounds may be of importance as intermediates for the production of dyes or biologically active substances gain. With the invention is to be achieved, the previously unidentified 2,5-diaryl-3,4-diar.ylimino-1,2,5-thiadiazolidine S-oxides to make accessible. This happens according to the invention in the way that tetraaryl-substituted oxalaraidins with thionyl chloride and a tertiary base to the above-listed compounds. The invention is in the chemical and pharmaceutical industry used

Description

4 49

A process for the preparation of 2,5-i) iaryl-3,4-diarylimino-1,2,5-thiadiazolidine S-oxides

Int. Cl. C07 D 285/10

Field of application of the invention

The invention relates to a process for the preparation of 2,5-diaryl-3,4-diarylimino-1,2,5-thiadiazolidine S-oxides. Such compounds may gain importance as intermediates for the production of dyes and biologically active substances.

Characteristic of the known technical solutions

2,5-Diaryl-3,4-diarylimino-1,2,5-thiadiazolidine S-oxides are hitherto unknown.

Object of the invention

The aim of the invention is to make the hitherto unknown 2,5-diaryl-3,4-diarylimino-1,2,5-thiadiazolidine S-oxides as precursors for dyes and biologically active compounds.

Explanation of the essence of the invention

The object of the invention is to make the previously unknown 2,5-diaryl-3,4-diarylimino-1,2,5-thiadiazolidin-S-oxides by simple reactions ", According to the invention this object is achieved in that tetraaryl -

'-! Il I) H, -so;

substituted oxalamidines of type I

with thionyl chloride in the presence of a tertiary amine such as <triethylamine, pyridine, quinoline or picoline to give the 2,5-diaryl-3,4-diarylimino-1,2,5-thiadiazolidine S-oxides of type II

II

1?

wherein R - R ° are the same or different and are hydrogen, an alkyl, .Aryl- or heterocaryl, an alkoxy group, a halogen atom or an amine function. The reaction proceeds at temperatures between 0 and 80 ⁰ C, preferably at 10-30 ⁰ C, as a solvent, hydrocarbons such as benzene, toluene or xylene but also chlorinated hydrocarbons such as tetra, chloroform or methylene chloride are suitable.

The desired 2,5-diaryl-3,4-diarylimino-1,2,5-thiadiazolidine S-oxides are obtained in high yields with short reaction times without the use of catalysts and drastic reaction conditions.

The oxalamidines used as starting materials are prepared by known methods, e.g. obtained by reaction of oxalanilides with phosphorus pentachloride and subsequent reaction of the resulting Oxalylarylimidchloride with primary aromatic amines.

embodiments

example 1

0.1 mol of Teträphenyloxalamidin be dissolved in 400 ml of dry benzene, treated with 0.25 mol of triethylamine and treated with vigorous stirring at room temperature within half an hour with 0.125 mol of thionyl chloride. Thereafter, the mixture is stirred for a further half an hour, then filtered and recrystallized after expelling the solvent.

P. 198 ⁰ C, yield 87% of theory 2,5-diphenyl-3,4-diphenylimino-1,2,5-thiadiazolidine S-oxide.

Example 2

From 0.1 mol of tetra-p-toluyl-oxalamidine according to Example 1

P. 178 ⁰ C, yield 86% of theory 2,5-di-p-toluyl-3,4-di-p-toluyl.-i.mino-1,2,5-thiadiazolidin-S-oxide.

Example 3

From 0.1 mol of tetra-p-anisidyl-oxalamidine in toluene as solvent according to Example 1

P. "102 ⁰ C, yield 88% of theory 2,5-di-p-anisidyl-3,4-di-p-anisidyl · imino-1,2,5-thiadiazolidin-S-oxide.

Example 4

From 0.1 mol of di-p-dimethylaminophenyl-diphenyl-oxalamidine after

example 1

P. 190 ⁰ C, yield 92% of theory 2,5-di-p-dimethylaminophenyl-3,4-diphenylimino-1,2,5-thiadiazolidin-S-oxide.

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Claims (1)

Claim of invention. A process for preparing 2,5-diaryl-3,4-diarylimino-1,2,5-thiadiazolidine S-oxides, characterized in that tetraaryl-substituted oxalamidines with thionyl chloride in an inert solvent and in the presence of a tertiary amine at temperatures of 0-80 ⁰ C, preferably at 10-30 ⁰ C to compounds of II where R - R ° are the same or different and denote hydrogen, an alkyl, aryl or heteroaryl radical, an alkoxy group, a halogen atom or an amine function.